Heat exchange rolls



May 10, 1960 B.'T.-RAMuNDo HEAT EXCHANGE ROLLS 2 Sheets-Sheet 2 FiledDec. 24, 1958 \\\\M Sk a INVENTOR. fav/mcs Z'A/va/vaa BY mgm.

' TTOR/VEY HEAT EXCHANGE ROLLS Boniface T. Ramundo, Cresskill, NJ.,assignor to Kentile, Inc., Brooklyn, N.Y., a corporation of New YorkApplication December 24, 1958, Serial No. 782,871

1 Claim. (Cl. 257-95) The invention herein disclosed relates to theconstruction of rolls suitable for calendering, sheeting, milling andthe like used `for various heat exchange purposes, includingheating,cooling, drying, calendering and the like.

f 'Special objects of the invention are to provide arstructure in whichheat transfer will be substantially equalized States Patent() over allportions of the roll surfaces and to accomplish 4 this result in asimple, readily manufactured, low cost form of construction.

Particularly it is a purpose of the invention to provide a roll withthese advantages which will be made up of but few parts and in whichsuch parts will contribute to the rigidity and strength of the roll plusthe desired roll surface characteristics of smoothness and hardness.

Further special objects of the invention are to simplify and improve theflow of circulating fluid enteri-ng and leaving the roll and to modifyfluid velocity beneath the surface of the roll to equalize or controlheat exchange without reducing contact with the sub-surface portions ofthe roll. i The foregoing and other` desirable objects are attained bythe novel features of construction, combinations and relations of partshereinafter described in detail and illustrated in the accompanyingdrawings.

In these drawings a present practical commercial embodiment of theinvention is illustrated but it will be appreciated that structure maybemodified and changed as regards such illustration'all within thetrueintent and scope of the invention as hereinafter defined andclaimed.

Fig. l in the drawings isa broken longitudinalsectional view of a rollembodying theinvention with the sectioned parts at opposite ends ofthisview appearing as taken on different planes, that at the left endappearing V as taken on the plane of line A A of Fig. 2, through radialexit channels and that at the right hand end appearing as taken throughradial inlet channels on line B B of Fig. 3.

Fig. 2 is a transverse sectional view of the roll on a planeintersecting the radial outlet passages on the plane indicated by line 22 of Fig. l.

Fig. 3 is a similar transverse sectional view on a plane intersectingthe radial inlet passages as on line 3 3 of Fig. l.

Fig. 4 is a broken plan illustrating the course of the labyrinthcirculating passages, this view showing appearance of the body or coreof the roll with the circulating grooves in the periphery of the same,before mounting of the surface shell thereon.

Figs. 5 and 6 are broken cross sectional views as on substantially theplanes of lines 5 5 and 6 6 of Fig. 4 showing particularly themodification of the groove cross section to effect acceleration of theow in the mid-length portions of the roll.

In a preferred development of the invention the roll is made up of buttwo main parts, a cylindrical body or core 7 selected and designed toprovide the desired ICC strength and rigidity and a surrounding sleeve`8 providing the required smooth hard surface characteristics.

The outer sleeve or shell in this combination requires but littlemachining and finishing and therefore it is economically possible tohave this shell just as hard and brittle as need be to provide the bestrolling, pressing and heat transfer surface characteristics. Thisprovides a means of control of hardening by heat treatment, carburizingor separate application of wear resistant materials, all accomplished byusing this separate shell.

The core, on the other hand, may be of tough but readily machinedmaterial selected to provideall needed strength and rigidity necessaryfor heavy duty rolling applications together with the proper journalstrength, shape and other design characteristics.

Maximum equalized heat transfer is edectcd by provision of shallowcirculating channels in the periphery of the core, underlying andcovered by the shell.

These channels, indicated at 9, may be formed by grooves machined in thesurface of the core orbe otherwise provided as by applying stripsdefining such grooves to the outer surface of the core as indicated at10 in Figs. 2, 3, 5 and 6.

As a further variation these circulating channels may be provided by aseparately formed cage having the grooves cut therein and secured inposition over the core, between the core and shell. These groovedefining strips or the cage described may be welded or otherwise securedin position on the core and similarly the shell may be secured in placeby welding or be shrunk onto the core.

In the illustration the circulating uid is introduced and taken off atone end of the roll by a swivel connection 11 which may be ofconventional design, fitted to the journal 12 at that end of the core. i

To accommodate this inflow and outflow the core yis made with a centerpassage extending through this one journal to the far end of the coreand this passage of a larger diameter at 13 in the journal to carry Howin both directions and of a lesser diameter at 14 in the body of thecore and a portion 15 of still less diameter in the far end portion ofthe core. V Separation of inowing and outliowing tiuid is effected by astationary section 16 of the supply pipe 17, extend` ing from the swivelfitting in through the center of the larger chambered portion 13 of theconduit and carrylng at the innertend a rotary Amechanical seal 18 forthe section 19 at the inner end of the pipe and which latter projectsthrough a sealing disk 20 seated in the core at the inner end of chamber13 into passage 14.

T his sealing disk 20 centers and supports the inner section 19 of inletpipe and it is shown as itself centered and supported in an annularshouldered seat 21 in the roll body at the inner end of passage 13.

The rotary seal is shown as carrying an annular shoulder 22 engaged withthe outer face of the sealing disk and by which pressure may be appliedto assist in holding the disk firmly engaged in the seat 21.

The circulating fiuid entered by the inner pipe section passes onthrough the reduced and further reduced sectlons 14 and 15 to radialsupply passages or ports 23 which are in communication with the thermaldistribution channels 9 at the far end of the roll.

From these channels the flow is by way of radial outlet ports orpassages 24 into the larger passage or chamber 13 in journal 12 into theouter cham-ber of the swivel fitting and thence out through outletpiping 25.

To distribute flow as evenly as possible and equalize temperature aboutthe surface of the roll the distributing channels 9 are connected ingroups, four groups in the case illustrated with three channels to eachgroup.

Fig. 3 shows the four radial supply passages Z3 and the diagrammaticview Fig. 4 shows one of these supply passages opening into the ends ofadjoining distributing channels 9. Each of these channels, at the otherend of the roll is in communication by a retum flow connection 26 with'the adjoining channel and the latterby a return connection 27 is incommunication with the next adjoining channel and the latter terminatesin communication with a radial outlet port 24.

Figs. 4, 5 and 6 show how in the illustration with a common inlet foradjoining channel sections and with a separate. outlet for each channelsection there will be four radial inlet passages 23 at the far end ofthe roll and eight outlet passages 24 in the near end of the roll. Thisnumber and arrangement may be varied to suit different requirements andif desired a separate inlet for each run of the distributing channelsmay be provided instead of the common inlet for adjoining sections. Alsoinstead of having separate outletsfor different channel sections,adjoining sections may have a common outlet, these being points fordetermination in designing the rolls for special purposes.

While distribution of the thermal circulating fluid may be substantiallyequalized by dividing that ilow into sections of a limited number oflongitudinal passes, three each in the illustration, it is found thatgenerally results may be improved by accelerating the ow across theactive mid-length portions of the channels by contracting the mid-lengthportions of these channels as illustrated at 28 in Figs. 4, 5 and 6.l

This may be accomplished `by reducing the cross sectional Vdimensions inthe formation of the channels, one practical method being by deposit ofwelding metal in securing the channel strips in place on the core, ifthe channels are provided by applying strips ora cage as described, orby depositing weld metal in the v,bottoms of the grooves if the channelsare formed by milling grooves in the surface of the core. v

By depositing metal in the bottom and lower corners of the grooves inthe nature of llets, the flow is restricted and 'acceleration andturbulencercreated thus to accomplish more effective heat transfer,without limiting the area of uid contact with the shell. These groovesare shallow, narrow and Vrelatively close together to effect maximumheat transfer and with that maximum support of the shell, a conditionnecessitated by the heavy pressure applications associated withcalendering, sheeting, milling and the like, which require that a.definite ratio of supported to unsupported shell to core area bemaintained. The shell backed up and fully supported by the lands betweenthe grooves can be as thin as considered best for heat transferpurposes.

The dam for separating the outowing from the inflowing iluid isparticularly simple and effective and is readily installed bycounterboring or forming the step 21 at the entrance to the core bodyproviding a seat into which the sealing disk can be forced. Thus seatedthe disk provides a centering support forthe inner end portion of thestationary supply piping.

What is claimed is:

A process roll comprising a heavy core of readily machined materialforming the body of the roll and a light thin shell of hard, heattreated material on said core and forming the working surface of theroll, said core having a cylindrical body portion with journalextensions at opposite ends of the same, `011e of said journalextensions having a ilow chamber extending inward from the end of thesame to said body portion and the body portion having a supply passagecontinued from said flow chamber to the opposite far end of the bodyportion and an annular seat at the junction of said ow chamber with saidsupply passage, said cylindrical body portion of the core havingexternal longitudinal fluid circulating grooves extending from end toend of the same, radial supply ports extending from the inner end of thesupply passage to said iiuid circulating grooves at that end of the bodyportion and radial exhaust ports extending from the opposite ends ofsaid grooves to the inner end of said flow passage, the thin shell beingxed over said body portion and covering the outer ends of said ports andsaid grooves, a dam engaged in said seat to rotate with the roll andseparating said supply passage from said flow chamber, a stationarysupply pipe entered in said ow chamber with space about the same incommunication with the inner ends of said exhaust ports and forming anannular discharge passage in said How chamber about said pipe, a swivelfitting at the outer end of said journal extension supporting the outerend of said stationary supply pipe and in flow receptive relation withsaid annular discharge passage, said supply pipe having an extension atthe inner end of the same projecting through said dam into said supplypassage and a rotary seal on said supply pipeat the outer side of saiddarn and in sealing relation with said dam for sealing said'supplypassage oft' from said annular discharge passage and enabling said damto serve as a centering support for the inner end of said supply pipe.

References Cited in the le of this patent UNITED STATES PATENTS1,651,502 Banbury Dec. 6, 1927 2,677,899 Ohlson et al. May 11, Y19542,890,026 Marganski et al June 9, 1959 FOREIGN PATENTS 21,001 GreatBritain 1913

